Image forming apparatus, image forming method, and recording medium storing an image forming program

Abstract

An image forming apparatus can detect a foreign object promptly during homing operation. After starting the homing operation, the image forming apparatus determines whether or not a carriage stops moving by detecting motion or stop of the carriage until timing to change detecting when either the carriage reaches predetermined position or velocity of the carriage reaches predetermined value. If the image forming apparatus determines that the carriage stops moving, the image forming apparatus controls a main scanning motor to stop driving. After the timing to change detecting, the image forming apparatus detects load variation of the main scanning motor. If the load variation is detected, the image forming apparatus controls the main scanning motor to stop driving.

What is claimed is: 
     
       1. An image forming apparatus, comprising:
 a carriage with a recording head mounted therein and configured to move reciprocally back and forth; 
 a detector configured to detect a position or velocity of the carriage; and 
 a processor configured to control a driving source of the carriage in accordance with the detected position or velocity of the carriage by,
 controlling the driving source if the processor detects that the carriage has stopped moving, while the carriage is an acceleration stage; and 
 controlling the driving source if the processor detects a load variation of the driving source, while the carriage is in a constant velocity stage. 
 
 
     
     
       2. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, when the processor performs a homing operation that determines a home position of the carriage by striking the carriage against another component. 
     
     
       3. The image forming apparatus according to  claim 2 , wherein the processor is configured to identify a position where the carriage stops as the home position when the processor performs the homing operation. 
     
     
       4. The image forming apparatus according to  claim 3 , further comprising:
 a displaceable component, wherein the processor is configured to detect whether or not the determined home position is correct by detecting displacement of the displaceable component. 
 
     
     
       5. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, if the carriage moves a target distance. 
     
     
       6. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, when the carriage is located at one end of a recording medium on which the recording head forms an image in carriage moving direction. 
     
     
       7. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, when the carriage reaches a position where the recording head starts forming an image. 
     
     
       8. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, when detected velocity of the carriage exceeds a command velocity. 
     
     
       9. The image forming apparatus according to  claim 1 , wherein the processor is configured to switch from controlling the driving source upon detecting that the carriage has stopped moving to controlling the driving source upon detecting the load variation of the driving source, when a command velocity commanded to the driving source of the carriage reaches a target velocity. 
     
     
       10. The image forming apparatus of  claim 1 , wherein the processor is configured to control the driving source by providing a stop command to the driving source. 
     
     
       11. The image forming apparatus of  claim 1 , wherein the processor is further configured to perform a homing operation to set a home position of the carriage based on the controlling of the driving source in the acceleration stage and the constant velocity stage. 
     
     
       12. The image forming apparatus of  claim 11 , wherein the processor is further configured to determine whether the set home position of the carriage is correct. 
     
     
       13. The image forming apparatus of  claim 12 , wherein the processor is configured to determine that the set home position is correct if the processor detects a feeler indicating whether liquid exists in a heat tank of the carriage. 
     
     
       14. The image forming apparatus of  claim 13 , wherein the processor is configured to report a malfunction if the processor does not detect the feeler. 
     
     
       15. The image forming apparatus of  claim 1 , wherein the controlling includes applying a signal to the driving source in order for the driving source to stop driving the carriage. 
     
     
       16. The image forming apparatus of  claim 15 , wherein the signal is a pulse width modulated (PWM) stopping command. 
     
     
       17. The image forming apparatus of  claim 16 , further comprising:
 generating the PWM stopping command by varying a duty cycle of a PWM command prior to applying the PWM command to the driving source. 
 
     
     
       18. A method of controlling driving of a driving source of a carriage, comprising:
 detecting a position or velocity of the carriage in which a recording head is mounted and moves reciprocally back and forth; 
 controlling the driving source of the carriage in accordance with the detected position or velocity of the carrier by,
 controlling the driving source if the detecting detects that the carriage has stopped moving, while the carriage is an acceleration stage; and 
 controlling the driving source if the detecting detects a load variation of the driving source, while the carriage is in a constant velocity stage. 
 
 
     
     
       19. A non-transitory recording medium including a computer-program product, the computer-program product storing a program that, when executed by a processor, causes the processor to implement a method of controlling a driving of a driving source of a carriage, by:
 detecting a position or velocity of the carriage in which a recording head is mounted and moves reciprocally back and forth; and 
 controlling the driving source of the carriage in accordance with the detected position or velocity of the carrier by,
 controlling the driving source if the detecting detects that the carriage has stopped moving, while the carriage is an acceleration stage; and 
 controlling the driving source if the detecting detects a load variation of the driving source, while the carriage is in a constant velocity stage.